1. Field of the Invention
This invention relates generally to sterilizing systems, and more particularly, to a portable antimicrobial ultraviolet sterilizer for inactivating bacteria, viruses, fungi, prions, viroids and spores.
2. Description of Related Art
The use of portable sterilizing devices is known in the prior art. By way of illustration, medical facilities generally sterilize equipment by using autoclaves having a pressurized steam and superheated water process. This process is commonly used in microbiology, medicine, body piercing, veterinary science, dentistry, podiatry and metallurgy. Autoclaves are also used in curing carbon-fiber composite parts and rubber parts and for the treatment and sterilization of waste.
This steam sterilization process requires many steps and resources. A typical sterilization procedure using an autoclave requires distilled water, sterilization or biohazard bags, germicidal liquid spray wash, ultra sonic bathing and drying by air compressors.
Drawbacks of these autoclaves include high energy consumption, time waste due to multiple step disinfecting sequences, environmentally toxic and costly harsh germicidal chemicals, and the deteriorating effects of the steam process on stainless steel surfaces. There are also well known safety risks attendant with high power and high pressure machinery such as autoclaves, namely, where the water inside the autoclave has managed to become superheated, the pressure gauge may not indicate the presence of steam even though the temperature may be significantly higher than the local boiling point for water. If the autoclave is opened in this state and the superheated water is disturbed, a steam explosion becomes possible. This phenomenon can easily produce fatal burns to people in the vicinity of the explosion.
Other inherent limitations of this prior art technology exist because damp heat is used, and thus heat labile products (such as some plastics) cannot be sterilized this way or they will melt. Some paper or other products that may be damaged by the steam must also be sterilized another way.
The prior art sterilization systems such as steam autoclaving, even at increased temperatures, and ethylene oxide gas are not effective to prevent the transmission of prions and viroids via medical and surgical equipment. Current sterilization methods for heat-resistant instruments involves at least a four step process of immersion in hypochlorite followed by autoclaving, followed by a wash and rinse and then routine sterilization methods. Autoclaving generally involves immersion in a sodium hydroxide solution. This has well known drawbacks since hypochlorite and sodium hydroxide may be corrosive to some instruments, such as gold-plated instruments. There is also associated damage to the autoclaves caused by the sodium hydroxide. Autoclaving involves high pressure with steam to attain high temperatures. There is condensate formation during the cycle and hazardous substances such as sodium hydroxide condensate in the autoclave that causes corrosion. Some sterilizer manufacturers have stated that this will void their warranty. Additionally, autoclaving with sodium hydroxide poses hazards to operators as a result of the caustic vapors.
UV sterilization is known for use and sterilizing all manners of objects, and is used in purification and disinfection of water, air and surface. Throughout the years ultraviolet technology has become well established as a method of choice for its effectiveness, economy, safety, speed, ease of use, and because the process is free of by-products. UV sterilization is a rapid sterilization method, without the use of heat or chemicals. However, this process has not been reduced in practice to a readily accepted device and method for common usage.
UV sterilizers take many shapes and forms, and offer a variety of features. While these prior art UV sterilizers are presumably adequate for their intended purposes, none of these prior art devices are configured adequately to a portable device or applications that can be used as commercial medical grade sterilization units that replace conventional autoclaves or for low cost portable home units.
Therefore, there is a need for a new UV sterilization system platform to expand on the prior art, and in particular, a system that provides a portable unit that can be adapted to many applications and overcome the limitations of the prior art. This technology will have a dramatic impact upon public health in third world countries.